Patient-specific orthopedic instruments

ABSTRACT

A method of preparing a distal femur for a knee joint implant includes mounting a patient-specific bone engagement surface of a femoral alignment guide on a complementary surface of a distal femur of a patient. A plurality of alignment pins is inserted through a corresponding plurality of guiding bores of the femoral alignment guide into the distal femur. A cutting guide is mounted on first and second alignment pins of the plurality of alignment pins, and a first resection of the distal femur is made using the cutting guide while cutting through the femoral alignment guide.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application is a divisional of U.S. application Ser. No. 12/995,361filed on Nov. 29, 2010, which is a continuation-in-part of (1.) U.S.application Ser. No. 12/938,905 filed on Nov. 3, 2010; and (2.) U.S.application Ser. No. 12/938,913 filed on Nov. 3, 2010; which is acontinuation-in-part of U.S. application Ser. No. 12/893,306 filed onSep. 29, 2010, which is a continuation-in-part of U.S. application U.S.application Ser. No. 12/888,005 filed on Sep. 22, 2010, now U.S. Pat.No. 8,377,066 issued on Feb. 19, 2013, which is a continuation-in-partof U.S. application Ser. No. 12/714,023 filed on Feb. 26, 2010, now U.S.Pat. No. 8,241,293 issued on Aug. 14, 2012, which is acontinuation-in-part of: (1.) U.S. application Ser. No. 12/571,969 filedon Oct. 1, 2009, which is a continuation-in-part of U.S. applicationSer. No. 12/486,992 filed on Jun. 18, 2009, and (2.) U.S. applicationSer. No. 12/389,901 filed on Feb. 20, 2009, now U.S. Pat. No. 8,133,234issued on Mar. 13, 2012, which is a continuation-in-part of U.S.application Ser. No. 12/211,407 filed on Sep. 16, 2008, which is acontinuation-in-part of U.S. application Ser. No. 12/039,849 filed onFeb. 29, 2008, now U.S. Pat. No. 8,282,646 issued on Oct. 9, 2012,which: (1) claims the benefit of U.S. Provisional Application No.60/953,620 filed on Aug. 2, 2007, U.S. Provisional Application No.60/947,813 filed on Jul. 3, 2007, U.S. Provisional Application No.60/911,297 filed on Apr. 12, 2007, and U.S. Provisional Application No.60/892,349 filed on Mar. 1, 2007; (2) is a continuation-in-part U.S.application Ser. No. 11/756,057 filed on May 31, 2007, now U.S. Pat. No.8,092,465 issued on Jan. 10, 2012, which claims the benefit of U.S.Provisional Application No. 60/812,694 filed on Jun. 9, 2006; (3) is acontinuation-in-part of U.S. application Ser. No. 11/971,390 filed onJan. 9, 2008, now U.S. Pat. No. 8,070,752 issued on Dec. 6, 2011, whichis a continuation-in-part of U.S. application Ser. No. 11/363,548 filedon Feb. 27, 2006, now U.S. Pat. No. 7,780,672 issued on Aug. 24, 2010;and (4) is a continuation-in-part of U.S. application Ser. No.12/025,414 filed on Feb. 4, 2008, now U.S. Pat. No. 8,298,237 issued onOct. 30, 2012, which claims the benefit of U.S. Provisional ApplicationNo. 60/953,637 filed on Aug. 2, 2007.

This application is a continuation-in-part of U.S. application Ser. No.12/995,361 filed on Nov. 29, 2010, which is a continuation-in-part ofU.S. application Ser. No. 12/872,663 filed on Aug. 31, 2010, now U.S.Pat. No. 8,407,067 issued on Mar. 26, 2013, which claims the benefit ofU.S. Provisional Application No. 61/310,752 filed on Mar. 5, 2010.

This application is a continuation-in-part of U.S. application Ser. No.12/995,361 filed on Nov. 29, 2010, which is a continuation-in-part ofU.S. application Ser. No. 12/483,807 filed on Jun. 12, 2009, now U.S.Pat. No. 8,473,305 issued on Jun. 25, 2013, which is acontinuation-in-part of U.S. application Ser. No. 12/371,096 filed onFeb. 13, 2009, which is a continuation-in-part of U.S. application Ser.No. 12/103,824 filed on Apr. 16, 2008, now abandoned, which claims thebenefit of U.S. Provisional Application No. 60/912,178 filed on Apr. 17,2007.

This application is a continuation-in-part of U.S. application Ser. No.12/995,361 filed on Nov. 29, 2010, which is a continuation-in-part ofU.S. application Ser. No. 12/103,834 filed on Apr. 16, 2008, now U.S.Pat. No. 7,967,868 issued on Jun. 28, 2011, which claims the benefit ofU.S. Provisional Application No. 60/912,178 filed on Apr. 17, 2007.

The disclosures of the above applications are incorporated herein byreference.

INTRODUCTION

The present teachings provide various patient-specific alignment andresection guides and associated instruments for knee arthroplasty.

SUMMARY

The present teachings provide an orthopedic device that includes apatient-specific alignment guide operable for preparing a bone of apatient for resection during joint arthroplasty. The alignment guideincludes a patient-specific bone engagement surface complementary to asurface of the bone of the patient and imaged from a bone scan of thepatient. The alignment guide includes a plurality of guiding bores and aplurality of alignment pins received through corresponding guiding boresfor attaching the alignment guide to the bone. The alignment pins areresorbable and can be sawn or cut off during a resection of the bone.

The present teachings also provide an orthopedic device that includes apatient-specific tibial alignment guide operable for preparing a tibiaof a patient for resection during joint arthroplasty. The tibialalignment guide includes a first portion engageable with a proximalsurface of the tibia and a second portion engageable with an anteriorsurface of the tibia. The first portion defines first and secondproximal guiding bores and an opening between the first and secondproximal guiding bores. The second portion defines first and secondanterior guiding bores and an elongated slot for guiding a blade forresecting the tibia. The tibial alignment guide also includes apatient-specific bone engagement surface defined by the first and secondportions and complementary to the proximal and anterior surface of thetibia. The orthopedic device further includes a plurality of alignmentpins receivable through respective proximal and anterior guiding boresfor attaching the alignment guide to the tibia. The alignment pins areresorbable and can be sawn or cut off during resection of the tibia.

The present teachings also provide a method of preparing a distal femurfor a knee joint implant. The method includes mounting apatient-specific bone engagement surface of a femoral alignment guide ona complementary surface of a distal femur a patient. The method alsoincludes inserting first and second resorbable anterior alignment pinsinto an anterior surface of the distal femur through corresponding firstand second anterior guiding bores of the femoral alignment guide, andinserting first and second resorbable distal alignment pins into adistal surface of the distal femur through corresponding first andsecond distal guiding bores of the femoral alignment guide. The methodfurther includes supporting a distal cutting guide on the first andsecond anterior alignment pins, passing a cutting blade through acutting slot of the cutting guide, and resecting the distal femur withthe cutting blade by cutting through the alignment guide and the firstand second distal alignment pins to form a resected distal surface.

Further areas of applicability of the present teachings will becomeapparent from the description provided hereinafter. It should beunderstood that the description and specific examples are intended forpurposes of illustration only and are not intended to limit the scope ofthe present teachings.

BRIEF DESCRIPTION OF THE DRAWINGS

The present teachings will become more fully understood from thedetailed description and the accompanying drawings, wherein:

FIG. 1 is an environmental perspective view of a patient-specificalignment guide with resorbable alignment pins according to the presentteachings;

FIG. 2 is an environmental perspective view of a patient-specificalignment guide with resorbable alignment pins shown cut through duringa distal resection according to the present teachings;

FIG. 3 is an environmental perspective view illustrating the cut-offcannulated alignment pins after a distal resection of the femuraccording to the present teachings;

FIG. 4 is an environmental view of a cutting guide mounted on thecut-off cannulated alignment pins of FIG. 3;

FIG. 4A is a side view of the cutting guide of FIG. 4;

FIG. 5 is an environmental perspective view of a patient-specificalignment guide according to the present teachings;

FIG. 6 is an environmental perspective view of a patient-specificalignment/resection guide according to the present teachings;

FIG. 7 is an environmental perspective view of a patient-specificalignment/resection guide of FIG. 6 shown with a guiding tool;

FIG. 7A is an environmental perspective view a guiding tool according tothe present teachings;

FIG. 8A is an environmental perspective view of a patient-specifictibial alignment/resection guide including a tool opening according tothe present teachings;

FIG. 8B is an environmental perspective view of a patient-specificalignment/resection guide including a tibial punch opening according tothe present teachings;

FIG. 9A is an environmental perspective view of a patient-specifictibial alignment/resection guide including an insert according to thepresent teachings; and

FIG. 9B is an environmental perspective view of a patient-specificalignment/resection guide including a tibial punch insert according tothe present teachings.

DESCRIPTION OF VARIOUS ASPECTS

The following description is merely exemplary in nature and is in no wayintended to limit the present teachings, applications, or uses.

The present teachings generally provide various patient-specificalignment and resection guides and other associated instruments for usein orthopedic surgery, such as, for example, in joint replacement orrevision surgery. The patient-specific guides can be used either withconventional or patient-specific implant components and can be preparedwith computer-assisted image methods. Computer modeling for obtainingthree-dimensional (3-D) images of the patient's anatomy using MRI or CTscans of the patient's anatomy, the patient-specific prosthesiscomponents, and the patient-specific guides and templates can bedesigned using various CAD programs and/or software available, forexample, by Materialise USA, Ann Arbor, Mich.

Patient-specific alignment guides and implants are generally configuredto match the anatomy of a specific patient. The patient-specificalignment guides are generally formed using computer modeling based onthe patient's 3-D anatomic image and have an engagement surface that ismade to conformingly contact and match a three-dimensional image of thepatient's bone surface (with or without cartilage or other soft tissue)in only one position, by the computer methods discussed above. Thepatient-specific alignment guides are designed and preparedpreoperatively using anatomic landmarks, such as osteophytes, forexample, and can be mounted intra-operatively without any registrationor other guidance based on their unique patient-specific surface guidedby the patient's anatomic landmarks.

The patient-specific alignment guides can include custom-made guidingformations, such as, for example, guiding bores or cannulated guidingposts or cannulated guiding extensions or receptacles that can be usedfor supporting or guiding other instruments, such as drill guides,reamers, cutters, cutting guides and cutting blocks or for insertingpins or other fasteners according to a surgeon-approved pre-operativeplan for performing various resections as indicated for an arthroplasty,joint replacement, resurfacing or other procedure for the specificpatient.

The patient-specific guides can also include resection or cuttingformations, such as cutting slots or cutting edges or planes guiding acutting blade to perform bone resections directly through thepatient-specific cutting guide. The patient-specific guides can be usedin minimally invasive surgery. Various alignment/resection guides andpreoperative planning procedures are disclosed in commonly assigned andco-pending U.S. patent application Ser. No. 11/756,057, filed on May 31,2007; U.S. patent application Ser. No. 12/211,407, filed Sep. 16, 2008;U.S. patent application Ser. No. 11/971,390, filed on Jan. 9, 2008, U.S.patent application Ser. No. 11/363,548, filed on Feb. 27, 2006; and U.S.patent application Ser. No. 12/025,414, filed Feb. 4, 2008. Thedisclosures of the above applications are incorporated herein byreference.

As disclosed, for example, in the above-referenced U.S. patentapplication Ser. No. 11/756,057, filed on May 31, 2007, in thepreoperative planning stage for a joint replacement or revisionprocedure, an MRI scan or a series of CT scans of the relevant anatomyof the patient, such as, for example, the entire leg of the joint to bereconstructed, can be performed at a medical facility or doctor'soffice. The scan data obtained can be sent to a manufacturer. The scandata can be used to construct a three-dimensional image of the joint andprovide an initial implant fitting and alignment in a computer file formor other computer representation. The initial implant fitting andalignment can be obtained using an alignment method, such as alignmentprotocols used by individual surgeons.

The outcome of the initial fitting is an initial surgical plan that canbe printed or provided in electronic form with corresponding viewingsoftware. The initial surgical plan can be surgeon-specific, when usingsurgeon-specific alignment protocols. The initial surgical plan, in acomputer/digital file form associated with interactive software, can besent to the surgeon, or other medical practitioner, for review. Thesurgeon can incrementally manipulate the position of images of variousimplant components in an interactive image of the joint. Additionally,the surgeon can select or modify resection planes, types of implants andorientations of implant insertion. After the surgeon modifies and/orapproves the surgical plan, the surgeon can send the final, approvedplan to the manufacturer.

After the surgical plan is approved by the surgeon, patient-specificalignment/resection guides can be designed using a CAD program or otherimaging software, such as the software provided by Materialise, forexample, according to the surgical plan. Computer instructions of toolpaths for machining the patient-specific alignment guides can begenerated and stored in a tool path data file. The tool path can beprovided as input to a CNC mill or other automated machining system, andthe alignment guides can be machined from polymer, ceramic, metal orother suitable material, and sterilized. The sterilized alignment guidescan be shipped to the surgeon or medical facility, for use during thesurgical procedure. Various patient-specific knee alignment guides andassociated methods are disclosed in the commonly assigned U.S.application Ser. No. 11/756,057, filed on May 31, 2007 (published as2007/0288030 on Dec. 13, 2007), which is incorporated herein byreference, and are now commercially available from Biomet ManufacturingCorp., Warsaw, Ind. in its Signature™ series.

The various patient-specific alignment guides can be made of anybiocompatible material, including, polymer, ceramic, metal orcombinations thereof. The patient-specific alignment guides can bedisposable and can be combined or used with reusable nonpatient-specific cutting and guiding components.

Referring to FIG. 1, an exemplary patient-specific femoral alignmentguide 100 according to the present teachings is shown mounted on thecorresponding patient's distal femur 80. The femoral alignment guide 100can have a light-weight body 101 with a patient-specific engagementsurface 102 that is complementary and made to closely conform and matewith a portion of the anterior-distal surface 84 of the patient's femur80 based on the pre-operative plan, as described above. The femoralalignment guide 100 can include a window/opening 104 and first andsecond distal guiding formations 106 defining guiding bores 107 forguiding corresponding distal alignment pins 120. The femoral alignmentguide 100 can also include first and second anterior guiding formations108 defining guiding bores 109 for guiding corresponding anterioralignment pins 122.

In the instruments and surgical techniques used with thepatient-specific alignment guides discussed in the commonly assigned andreferenced above U.S. application Ser. No. 11/756,057, filed on May 31,2007, the distal alignment pins may be spring drill pins or otherfasteners made of non-resorbable metallic biocompatible materials.Similarly, the anterior pins are metallic trochar pins or othernon-resorbable fasteners. After distal and anterior holes are drilledthrough the bone for the corresponding distal and anterior alignmentpins using the alignment guide, the alignment guide is removed. Theanterior alignment pins are guided through the anterior holes and adistal cutting block is mounted on the anterior alignment pins to make adistal resection as designed in the pre-operative plan. Similarly, afour-in-one or other cutting block is mounted over the distal alignmentpins to make the remaining the resections of the distal femur.Alternatively, the distal alignment pins can be removed and a cuttingblock having fixed or removable pins attached thereto can be mounted onthe femur by placing the pins of the cutting block into separate distalholes prepared using the alignment guide or into the distal holes fromwhich the distal pins were removed. In this manner, the distal andanterior holes and the corresponding distal and anterior alignment pinsare reference elements for referencing correctly the placement of thevarious cutting blocks and the corresponding resections. All thealignment pins are then removed and the prosthetic components areimplanted.

In contrast to the above method and according to the present teachings,the distal and anterior alignment pins are made of resorbable materials,such as polymers, and can be sawn or cut off during resection. Theportions remaining in the bone can be gradually resorbed, such that thestep of removing the alignment pins is eliminated. Referring to FIG. 2,for example, a distal cutting block 200 can be mounted over the anterioralignment pins 122 (only one is visible in the view of FIG. 2), whichcan pass through corresponding openings 204 of the distal cutting block200, while the femoral alignment guide 100 is still nested on the distalfemur 80. The alignment guide 100 is disposable and made of polymericmaterial that can also be sawn or cut off. The distal cutting block 200includes a cutting slot or other cutting guiding formation 202. Acutting blade 230 is guided through the cutting slot 202 and can makethe distal resection of the femur 80 sawing through the alignment guide100 and the resorbable distal alignment pins 120 to create a resecteddistal surface 82 shown in FIG. 3.

The resorbable distal alignment pins 120 can be cannulated having aninner bore 121 sized for receiving corresponding pins 242 coupled to a4-in-1 cutting block 240 for making anterior, posterior and chamfercuts, as shown in FIGS. 3, 4 and 4A. In this respect, the bores 121reference the location for the cutting block 240. The anterior alignmentpins 122 can be also sawn-off or cut-off while making the anterior cut.Alternatively, non-resorbable cannulated distal alignment pins, whichare mounted in corresponding pre-drilled holes, can be used for mountingthe 4-in-1 cutting block 240 on the resected distal femur 82. In otherembodiments, the pins of the 4-in-1 cutting block 240 can be cannulatedand slide over non-cannulated distal alignment pins 120. It will beappreciated that when using non-resorbable alignment pins, the alignmentpins that are not used to support and guide the cutting block can beremoved prior to resection to avoid interference with the resection.

In an alternative embodiment illustrated in FIG. 5, the first and seconddistal guiding formations 106 of a femoral alignment guide 100′ arepositioned obliquely, i.e., not perpendicularly relative to the surfaceof the medial and lateral condyles, such that the distal alignment pins120 do not obstruct the distal cut and need not be cut through orremoved. The femoral alignment guide 100′ can remain on the distal femur80 and can be cut through when the distal resection is made, asdiscussed above in connection with FIG. 2. The distal alignment pins 120can also be made of resorbable material that can be sawn or cut off.

Referring to FIG. 6, a representative tibial alignment/resection guide300 is illustrated according to the present teachings. The tibialalignment guide 300 can include a body 301 having a proximal portion303, an anterior portion 305 and a patient-specific bone engagementsurface 302 complementary and made to closely conform and mate with aportion of the anterior surface 72 and proximal surface 74 of thepatient's tibia 70 in only one position based on the pre-operative plan.The tibial alignment guide 300 can include first and second proximalguiding formations 306 defining guiding bores 307 for correspondingproximal alignment pins or other fasteners 123. The tibialalignment/resection guide 300 can also include first and second anteriorguiding formations 308 defining guiding bores 309 for correspondinganterior alignment pins or other fasteners 127. As discussed above inconnection with alignment guides in general and the femoral alignmentguide 100 in particular, the tibial alignment guide 300 can be used todrill reference holes for the corresponding proximal and anterioralignment pins 123, 127, which can then be re-inserted as needed foreach resection and corresponding resection block after the tibialalignment/resection guide 300 is removed. When using resorbablealignment pins, the alignment pins can remain and be sawn or cut offduring resection. In the embodiment illustrated in FIG. 6, the tibialalignment/resection guide 300 can include a resection guiding slot 310for guiding a tibial resection according to the pre-operative plan forthe patient. The tibial alignment/resection guide 300 can be optionallyused as a resection guide for resecting the tibia 70 through the guidingslot 310 with a blade or other resection tool while the tibialalignment/resection guide 300 is mounted on the tibia 70.

Referring to FIG. 7, when a tibial alignment/resection guide 300 that isdisposable and lightweight is used for making a resection, a metal orother more rigid guide tool 460 can be optionally used by the surgeonfor providing additional rigidity and stability for the surgeon whileguiding a resection blade 230 (shown in FIG. 2). The guide tool 460 caninclude an anterior portion 465 having an elongated slot 466, and aproximal portion 463 having first and second apertures 462 that can fitover the proximal guiding formations 306 of the alignment guide 300and/or the corresponding alignment pins 123, as shown in FIG. 7A. Theelongated slot 466 is aligned with the resection guiding slot 310 of thetibial alignment/resection guide 300 when the first and second apertures462 are aligned over the proximal guiding formations 306. The guide tool460 can also include a handle 450, which can be integrally or removablycoupled to the guide tool 460. Referring to FIG. 7A, the guide tool 460can also be used over the proximal alignment pins 123, after the tibialalignment/resection guide 300 is removed. Because the proximal alignmentpins 123 have been placed through the tibial alignment/resection guide300, the proximal alignment pins 123 correctly reference the guide tool460 and the elongated slot 466 of the guide tool 460 for guiding thetibia resection according to the pre-operative plan. A similar guidetool can be configured to be used over the anterior alignment formations308.

Referring to FIGS. 8A and 8B, tibial alignment/resection guides 350,370, similar in other respects with the tibial alignment/resection guide300, can include corresponding proximal openings 352, 372 between theproximal alignment formations 306. The openings 352, 372 can be shapedfor guiding various instruments. Referring to FIG. 8B, for example, theproximal opening 372 includes a plurality of fin-shaped slots 371configured in the shape a punch mask for guiding a finned stem punchthrough the proximal surface 74 of the tibia 70 along the direction ofthe intramedullary canal axis in preparation for a tibial stem implant.

Referring to FIGS. 9A and 9B, a tibial alignment/resection guide 390,can include an opening 392 for receiving a removable insert 400 or 425that is made of a more rigid material, such as, for example, metal ormetal alloy. The inserts 400, 425 can be simply placed in the opening orremovably coupled by a snap-fit engagement or by a frictional or othermechanical coupling. The inserts 400, 425 can include a correspondingopening 402, 426 shaped for guiding an instrument. The opening 426 ofthe insert 425, for example, includes a plurality of fin-shaped slots423 shaped to guide a finned stem punch along the intramedullary canalaxis in preparation for a tibial stem implant. Each of the inserts 400,425 can be used with a modular handle 450 that can be removably coupledwith the corresponding insert by a tongue-and groove, dovetail or othercoupling arrangement between a distal portion 452 of the handle 450 anda mating portion 404 or 428 of the corresponding insert 400, 425(details not shown). A plurality of inserts can be provided forselective use by the surgeon in terms of preference or in combinationwith various punches and corresponding tibial stems.

The various alignment/resection guides described above (100, 100′, 300,350, 370, 390) can be made of biocompatible polymeric or other plasticmaterials and are disposable. The alignment/resection guides can be cutthrough while making various resection cuts. The various alignment pinscan be metallic or resorbable. Resorbable pins can be cut off or sawnoff or broken off by hand with portions remaining in the bone andresorbed over time. The various alignment/resection guides can also befrangible along score lines or either intentionally weakened portions ofthe alignment/resection guides. Alternatively, the alignment/resectionguides can have modularly coupled portions that can be optionallyremoved, for example, before performing a resection. Additional detailsfor alignment/resection guides with frangible and/or modularly coupledportions are disclosed in commonly assigned and co-pending patentapplication Ser. No. 12/571,969, filed Oct. 1, 2009 and published as2010-0087829 on Apr. 8, 2010, the disclosures of which are incorporatedherein by reference.

The foregoing discussion discloses and describes merely exemplaryarrangements of the present teachings. Furthermore, the mixing andmatching of features, elements and/or functions between variousembodiments is expressly contemplated herein, so that one of ordinaryskill in the art would appreciate from this disclosure that features,elements and/or functions of one embodiment may be incorporated intoanother embodiment as appropriate, unless described otherwise above.Moreover, many modifications may be made to adapt a particular situationor material to the present teachings without departing from theessential scope thereof. One skilled in the art will readily recognizefrom such discussion, and from the accompanying drawings and claims,that various changes, modifications and variations can be made thereinwithout departing from the spirit and scope of the present teachings asdefined in the following claims.

1.-20. (canceled)
 21. An orthopedic system comprising: apatient-specific alignment guide operable for preparing a bone of apatient during joint arthroplasty, the alignment guide including apatient-specific bone engagement surface configured to be complementaryto a surface of the bone of the patient, the alignment guide including aplurality of guiding bores; a plurality of alignment pins receivablethrough corresponding guiding bores for attaching the alignment guide tothe bone, wherein the alignment pins are configured to be cut off duringa first resection of the bone; and a cutting block mountable to aportion of the one or more of the plurality of alignment pins thatremain in the bone after being cut off, the cutting block configured toguide a second resection of the bone.
 22. The orthopedic system of claim21, wherein the plurality of alignment pins are cannulated andconfigured to receive mounting projections of the cutting block thereinto mount the cutting block into a desired position relative to the bone.23. The system of claim 21, wherein the first resection is to a distalportion of the bone, and wherein the second resection is to an anteriorportion of the bone.
 24. The system of claim 21, wherein the alignmentpins are configured to be cut off during both the first resection of thebone and the second resection of the bone.
 25. The system of claim 21,wherein the patient-specific alignment guide is configured with a slotto facilitate the first resection.
 26. The system of claim 21, whereinthe plurality of alignment pins are resorbable.
 27. The system of claim21, wherein the patient-specific alignment guide comprises a tibialalignment guide and the bone comprises a tibia, the tibial alignmentguide including: a first portion engageable with a proximal surface ofthe tibia, the first portion defining a first and a second of thecorresponding guiding bores and an opening between the first and thesecond of the corresponding guiding bores; and a second portionengageable with an anterior surface of the tibia, the second portiondefining a third and a fourth of the corresponding guiding bores. 28.The system of claim 21, wherein the plurality of guiding bores includesa pair of oblique guiding bores oriented at an oblique angle relative toa surface of a distal femur.
 29. The system of claim 21, wherein thepatient-specific alignment guide comprises a femoral alignment guide andthe bone comprises a femur, the femoral alignment guide including: afirst portion engageable with a distal surface of a femur, the firstportion defining a first and a second of the corresponding guidingbores; and a second portion engageable with an anterior surface of thefemur, the second portion defining a third and a fourth of thecorresponding guiding bores.
 30. An orthopedic system comprising: analignment guide operable for preparing a bone of a patient during jointarthroplasty, the alignment guide including a plurality of guidingbores; a plurality of alignment pins receivable through correspondingguiding bores for attaching the alignment guide to the bone, wherein thealignment pins are configured to be cut off during a first resection ofthe bone; and a cutting block mountable to a portion of the one or moreof the plurality of alignment pins that remain in the bone after beingcut off.
 31. The orthopedic system of claim 30, wherein the plurality ofalignment pins are cannulated and configured to receive mountingprojections of the cutting block therein to mount the cutting block intoa desired position relative to the bone.
 32. The system of claim 30,wherein the alignment guide includes a slot to facilitate a firstresection to a distal portion of the bone, and wherein the cutting blockincludes a slot to facilitate a second resection to an anterior portionof the bone.
 33. The system of claim 32, wherein the alignment pins areconfigured to be cut off during both the first resection of the bone andthe second resection of the bone.
 34. The system of claim 30, whereinthe plurality of alignment pins are resorbable.
 35. The system of claim30, wherein the alignment guide comprises a patient-specific guidehaving a patient-specific bone engagement surface configured to becomplementary to a surface of the bone of the patient.
 36. An orthopedicsystem comprising: an alignment guide operable for preparing a bone of apatient during joint arthroplasty, the alignment guide including aplurality of guiding bores; a plurality of alignment pins receivablethrough corresponding guiding bores for attaching the alignment guide tothe bone, wherein the alignment pins are cannulated and configured to becut off during a first resection of the bone; and a cutting blockmountable to a portion of the one or more of the plurality of alignmentpins that remain in the bone after being cut off.
 37. The system ofclaim 36, wherein the alignment guide includes a slot to facilitate afirst resection to a distal portion of the bone, and wherein the cuttingblock includes a slot to facilitate a second resection to an anteriorportion of the bone.
 38. The system of claim 37, wherein the alignmentpins are configured to be cut off during both the first resection of thebone and the second resection of the bone.
 39. The system of claim 36,wherein the alignment guide comprises a patient-specific guide having apatient-specific bone engagement surface configured to be complementaryto a surface of the bone of the patient.
 40. The system of claim 36,wherein the plurality of guiding bores includes a pair of obliqueguiding bores oriented at an oblique angle relative to a surface of adistal femur.